Figure S6 Effects of warming (W), nitrogen addition (N) and their
interactions on plant density, plant height and plant coverage of
C3 plants and C4 plants from 2013 to
2022, based on a repeated-measures analysis of variance (ANOVA).
Uppercase letters indicate significant difference in the plant density,
plant height and plant coverage of C3 and
C4 plants among treatments determined by Tukey’s HSD
test at P <0.05.